hmm, i have many male friends that didn't make a pass on me or our other female friends ever. because we are, ummm, friends. and i have plenty monogamous friends, too.
This topic is raised occasionally amongst guys, and the generally consensus is that there aren't many at all of our female friends that we wouldn't sleep with (though it's more accurate to say 'that we aren't sexually attracted to).
From my perspective there's only ever been one female friend who I wasn't sexually attracted to - it's a bizarre and unsettling feeling when you meet a girl like this for the first time...and all I could think is "I can't ever tell her this, because it would be very insulting".
That said, there's many reasons we don't sleep with our friends :
- morals (if they are in a relationship)
- they aren't interested in us (usually more the case)
- you/they emotionally aren't able to handle casual sex without the friendship eventually ending (ie the friendship is more important than the sex)
- the guy is too much a 'nice guy' (this works both ways)
Now getting on to the OP : I'm of the opinion that friends (of any sex) are the province of the individual, not the couple. The wife has no right to tell a husband to end a friendship, nor visa versa.
As for the question of whether or not one is interested in the other, see above. That doesn't mean he 'wants to sleep with her' - one part can want to...and lets face it, without attraction to females he would never have married you...while another part does not want (for whatever reasons, morality, committment to you, love of you, etc). For her part, if she's calling him because she's bored, rather than because he's her friend - yeah that could be cause for worry...but the only couple you truly have to look at, is him and you.